Simple Files: Read, add, modify and delete lines from text files

This class can be used to read, add, modify and delete lines from text files.

It can open an existing file or create a new one.

The class can retrieve the file lines into an array, optionally keeping only those that match a given content criteria.

It can also sort the returned lines or limit the number of lines that are returned just like with SQL database queries.

The class can also modify or delete the file lines according to a content condition.